In other words, this map depicts the percentage of children in each country who are dangerously underweight on account of malnutrition. (Quantifying just how underweight these children are is difficult without knowing the variation in weight in the study population.) Data are from 1990 to 2002 and countries in blue indicate no data was available.

In parts of Sudan and Niger, half of all children suffer from malnutrition.(Per Square Mile/Tim De Chant)

That belt of red stretching from Africa through India, encompassing tens of millions of children, represents perhaps the biggest waste of human capital in history. Children who suffer from malnutrition are more susceptible to disease, less capable of getting an education and are likely to suffer from permanently stunted growth.

Parts of Pakistan and India have proportions of underweight children as bad or worse than war-torn regions of Africa.(Per Square Mile/Tim De Chant)

Many of the regions experiencing highest population growth are also the ones suffering the highest rates of child hunger.